The present invention relates to a hot melt glue gun and, more particularly, to an improved hot melt glue gun using electricity to generate high heat for melting a glue stick.
A type of an automatic hot melt glue gun includes a gun-shaped housing and a press button coupled to the housing. A glue stick feeding device and a hollow hot melt unit are mounted in the housing. The glue stick feeding device includes a transmission gear and a plurality of gears. The plurality of gears form a passage through which a glue stick extends. The hot melt unit is aligned with the passage. When the press button is pressed, the transmission gear rotates to move the glue stick forwards, pushing molten glue in the hot melt unit to flow out of a nozzle. An example of the automatic hot melt glue gun is disclosed in U.S. Pat. No. 9,586,229 B1 entitled “HOT MELT GLUE GUN WITH AN AUTOMATIC GLUE STICK FEEDING STRUCTURE.”
However, in the above conventional automatic hot melt glue gun, when a distal end of the glue stick moves forwards and, thus, leaves the plurality of gears, since the glue stick feeding device is hidden in the housing, the user cannot know if there are no glue sticks left in the passage. If the user continues to press the press button, the transmission gear and the plurality of gears rotate idly, and there is no molten glue flowing out of the outlet, resulting in interruption of supply of glue. Even if a new glue stick is inserted immediately, a spacing exists between the front end of the new glue stick and the rear end of the preceding glue stick, which also causes interruption of supply of glue, rendering discontinuous operation. Consequently, the conventional automatic hot melt glue gun is inconvenient to use.
Thus, improvement to the conventional automatic hot melt glue gun is necessary.